Railcar movers provide a more efficient way to move railcars around within a rail yard than using a locomotive for such tasks. The railcar movers while efficient at moving railcars may sometimes move the railcars around the rail yard at a speed that may be unsafe depending upon the conditions within the rail yard. A means to control the maximum speed of the railcar mover, while still allowing the engine of the railcar mover to reach a full power mode for accelerating when travelling below the maximum speed would enhance safety conditions within the rail yard.